dynamic scheduling by Julia - julia

Question

I have a function for dynamic scheduling and I can use it for simple array and functions, for example I can use it for this code:
scheduling:
#everywhere function pmap(f,lst)
np=nprocs()
n=length(lst)
results=Vector{Any}(n)
i=1
nextidx()=(idx=i;i+=1;idx)
#sync begin
for p=1:np
if p != myid() || np==1
#sync begin
while true
idx=nextidx()
if idx > n
break
end
results[idx]= remotecall_fetch(f,p,lst[idx])
end
end
end
end
end
results
end
function:
#everywhere f(x)=x+1
f (generic function with 1 method)
array:
julia> arrays=SharedArray{Float64}(10)
10-element SharedArray{Float64,1}:
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
0.0
julia> arrays=[1 2 3 4 5 6 7 8 9 10]
1×10 Array{Int64,2}:
1 2 3 4 5 6 7 8 9 10
result:
#everywhere function fsum(x)
x+1
end
pmap(fsum,arrays)
10-element Array{Any,1}:
2
3
4
5
6
7
8
9
10
11
my question is if I had this function and arrays, how should I use scheduling function?
function:
#everywhere f(x,y)=x.+y
julia> x=SharedArray{Float64}(2,2)
2×2 SharedArray{Float64,2}:
0.0 0.0
0.0 0.0
julia> y=SharedArray{Float64}(2,2)
2×2 SharedArray{Float64,2}:
0.0 0.0
0.0 0.0
julia> x=[1 2;3 4]
2×2 Array{Int64,2}:
1 2
3 4
julia> y=[6 7;8 9]
2×2 Array{Int64,2}:
6 7
8 9
I wanted to call it by pmap(f,x,y) but I got this error:
ERROR: MethodError: no method matching pmap(::#f, ::Array{Int64,2}, ::Array{Int64,2})
You may have intended to import Base.pmap
Closest candidates are:
pmap(::Any, ::Any) at REPL[1]:2
and I have another question too, How we can be sure our problem is running in different process? How we can monitor it?

Answer 1

pmap splats the arguments, and so this works:
f(x,y) = x+y; pmap(f,1:5,6:10)
You probably re-defined pmap using what you have in the OP which doesn't splat the arguments and thus fails. You do not need to write your own here: if you just use the built-in version it will work.